In general, an apartment building, office building or other human life space has a bathroom(s). In the past, the bathroom was placed at a location isolated from the living space to treat the human excreta. However, a recent trend is towards the bathroom being housed inside the living space as the apartment is favored as a dwelling.
Following such trend, the toilet and basin installed in the bathroom goes on evolving for more sanitation. Further, a change in function of the bathroom from a mere space to treat human waste to a multi-functional room for bathing and makeup led to people staying longer in the bathroom, and the waste treatment space is thus in the trend of being equipped with higher-class facilities.
Meanwhile, an air exhausting facility mostly comes with the bathroom of an apartment house. The air exhausting facility is installed on a ceiling panel inside the bathroom, and a fan is provided on the top or a side of the facility for smooth exhaust. The air exhausting system draws the moisture or odor out of the bathroom.
However, such air exhausting facility simply exhausts air from the bathroom and cannot respond to the satisfaction when the bathroom door remains closed, i.e., in the airtight bathroom.
In other words, although for ventilation an air intake should be the same as the amount of air exhaust, the air intake in the door-closed state fails to reach the amount of air exhaust, thus rendering ventilation difficult.